You (65 kg) are standing in an elevator traveling upward that passes the 3rd floor at 3.5 m/s and then passes the 4th floor at 4.5 m/s one second later. Find the normal force exerted on your feet by the elevator while it is passing between these floors.

I got 6565 N, because acceleration is 1, Fnet = ma which is 65, and WE1 is -6500 N, but that isn't the right answer.